I'm biased, of course, but I think Ash is pretty edgy and cool for a girl. The options are pretty limited to Ashley, Ashlyn/Ashton (or the traditional Irish spelling, Aisling/Aislinn), and Asha. Not very exciting, haha.

Or, you could go the other way around: a unisex name that comes with a girly nickname:

For some reason I really like Penelope nn Poppy for you, too--you get the floral with Poppy, it's an unusual nn (even though Penelope's growing in popularity), and I find it really strong, thanks to Odysseus's wife in The Odyssey, but it also has a frilly sort of sound, which might appeal to your husband. It's not rabidly popular, but familiar enough that I don't think you'd have issues with. If you don't like Poppy for a nn, there's also Pen/Penny, Nell, Lola, Pepper, Piper, Pippa, even Ella... I think it's versatile and lovely, and I think Matthew, Benjamin, and Penelope are lovely.

What are the names you have liked so far? And him? That might give us a better idea of what to suggest. (Also, your husband sounds adorable, haha. I can only hope that when I have a little girl in the future, and potential husband of mine would get so excited!)